Can Trump Go To War With North Korea? Not Without Congress, Says the New York City Bar Association

Donald Trump is waging a war of words with North Korean leader Kim Jong Un. But the New York City Bar Association has told the president he needs congressional authority to declare war on the rogue state. STR/AFP/Getty

Updated | Donald Trump lacks the authority to take military action against North Korea unless that country poses an immediate threat or if Congress grants approval, New York City's biggest legal group told the president.

Trump has the authority to take "defensive action against an actual or imminent threat," but the "power to authorize other military actions constituting acts of war lies exclusively with Congress, which can act either through a formal declaration of war or other legislation," John Kiernan, president of the New York City Bar Association, which has 25,000 members, wrote in a letter announced on Tuesday.

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To consider a threat "imminent," it must be "instant, overwhelming, and leaving no choice of means, and no moment for deliberation," the letter said.

So far, of course, the battle has been one of words. Trump has threatened North Korea and its leader, Kim Jong Un, saying that the United States "will have no choice but to totally destroy North Korea." A month earlier, he said that if North Korea continued to make threats, the rogue state "will be met with fire and fury like the world has never seen." He has also tweeted that Secretary of State Rex Tillerson "is wasting his time trying to negotiate" with the country.

North Korea has responded in kind, calling President Trump a "dotard," and has tested long-range missiles and nuclear explosives.

But it's not enough to meet the threshold of "imminent" need for an attack. "Mere rhetorical bluster and displays of military prowess or weapons by a foreign leader do not meet this test," the letter said.

Nor does North Korea's development of its nuclear program, the letter added.

Without Congress, the president can deploy forces for just 60 days, thanks to the War Powers Resolution, which Congress passed in 1973. Since the September 11 attacks, the president can also order the use of force against countries that helped plan or carry out those attacks, through the Authorization for the Use of Military Force law.

But, as Kiernan noted, North Korea has never been accused of participating in those attacks.

"We do think it's important to weigh in on whether there's legal authority, and we don't find it, absent an actual or imminent attack against us or possibly against our allies," Mark Shulman, chairman of the bar association's Task Force on National Security and the Rule of Law, tells Newsweek. "These are not laws created by egghead legal scholars like me. They're very practical laws intended to produce stability, predictability and security for the nations that have created them."

If Trump asks Congress to approve action against North Korea, he might not be met with total resistance. Senator Lindsey Graham, a Republican, told conservative commentator Hugh Hewitt in August, "It would be very smart if the Congress could come together and tell the president, 'You have our authorization to use military force to stop the threat to the homeland as a last resort.' That would send a signal to North Korea and China that would probably do more good to avoid war than anything I can think of."

But other lawmakers have condemned Trump's handling of the North Korean threat. Senator Ed Markey, a Democrat from Massachusetts, tweeted on Tuesday, "We must all stand up to Trump and his rhetoric that could lead to #nuclear war w/#NorthKorea. Congress must be the check on his authority."

Another Democratic senator, Chris Murphy, from Connecticut, tweeted on Monday, "It's time to take Trump seriously as he keeps hinting, over and over, that he wants to go to war with North Korea." He added, "Now is time—before it's too late—for Rs [Republicans] and Ds [Democrats] to make clear no preemptive strike against NK can happen without a vote by Congress."

In August, more than 60 members of Congress wrote to Tillerson that the Trump administration should "publicly declare its agreement with the constitutional requirement that any preemptive attack on North Korea must be debated and authorized by Congress."

This article has been updated to include a comment from Mark Shulman of the New York City Bar Association.